Can one visitor be assigned to multiple Variation Groups in the same Campaign?

SiteSpect stores session information about visitors using HTTP cookies, which is powerful but not without drawbacks. One drawback is that it is possible for a visitor to be assigned to more than one Variation Group within the same Campaign. This can happen in the following situations:

  • A returning visitor is about to start a new SiteSpect session and opens multiple tabs at the same time. The last tab that loads overwrites the assignments of the other tabs and persists. This can happen in any of the following scenarios:
    • The visitor is on a search results page and opens multiple links to a SiteSpect site in multiple tabs.
    • The visitor's browser previously closed or crashed, the visitor had multiple tabs open to a SiteSpect site and she restores all tabs when starting.
    • The visitor has a bookmark folder with multiple links to a SiteSpect site and uses the Open all Bookmarks option.
    • Someone or something makes parallel non-standard pre-fetch (but not using the standard 'X-moz: prefetch' header) requests made to a non-SiteSpect site.
  • The visitor periodically uses a cookie sync between devices and/or browsers. If the sync doesn't happen often enough, it is possible that the GUID might go through assignment logic for each device and end up with different assignments (which are overwritten after the next sync).
  • A program replays a visit using a fixed set of SiteSpect cookies in which the visitor passes the robot test.